This is the scar a man received on his arm after being struck by lightning. It's a Lichtenberg Figure, or the pattern made from an electrical discharge. As you can see, it's kinda flowery. Still beats the shit out of any tribal tat though.

HA! Before I decided to write 'He's going to get so much lay thanks to that scar and story' I read some of the comments. This is what I found; "He's a redhead, isn't he. Look at those freckles! AND struck by lightening AND cool scar? I'm in love. Forward him my contact info. "